Traditional methods for workspace navigation have not changed much over the past decade. A common method of navigating a workspace is to use a hierarchical tree structure to store and display the contents of the workspace. For example, the start menu, introduced in MICROSOFT's WINDOWS 95 operating system and included in MICROSOFT's latest operating system offering, has remained almost unchanged. The start menu provides access to applications and files using a tree structure. As society progresses further into the Digital Age, the amount of data available to users continues to grow at a tremendous rate. Likewise, the number of applications, including open-source software and web-based applications, available to view, create, and edit that data has also grown. Using a tree structure to navigate a workspace with such a large amount of data and applications may be inadequate, or at least inefficient.
Tree structures may be unable to organize the massive number of applications available in a manner that is easily navigated. To accommodate a large number of applications, tree structures may need to increase either the number of items at a particular level of the tree or increase the number of levels used by the tree. As the number of items in the tree increases, the tree may become unusable because of the number of levels and/or the long list of items contained in each level of the tree. The inability for an item to be located in two different places in the tree may be another disadvantage of traditional tree-structure navigation systems. Another inconvenience of using a tree structure is that a typical tree-structure menu may reset its state after a user selects an item. For a tree with many levels, this may be inconvenient. Other disadvantages of tree-structure systems may include the difficulty of changing the location of items in the tree and the inability to place two similar items close together in the tree.